I've been doing EPP. While I mostly glue baste medallion by medallion, if I know I won't get back to the medallion for a few days I use left over thread to baste my pieces. I also use up extra thread in bobbins and for basting.
I'm curious, why you can wind your thread off the spool onto a bobbin and use it? I guess I don't understand why if they aren't wound evenly on the spool, they can't be wound onto a bobbin and used. I guess I've never run into that.